Compiling silc-client fails - sv_undef not defined

[D. Mitchell]

gcc -DHAVE_CONFIG_H -I. -I. -I../.. -I../../src -I../../src/core -I../../src/
fe-common/core -I../../src/fe-common/silc -I/usr/incl 
ude/glib-1.2 -I/usr/lib/glib/include -DSCRIPTDIR=\"/usr/local/share/silc/
scripts\" -DPERL_USE_LIB=\"/usr/local/lib/perl5/5.8.8/i686 
-linux-64int-ld\" -DPERL_STATIC_LIBS=0 -fno-strict-aliasing -pipe 
-Wdeclaration-after-statement -I/usr/local/include -D_LARGEFILE_S 
OURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm -I/usr/lib/perl5/5.8.8/
i686-linux-64int-ld/CORE -O6 -Wall -MT perl-core.lo -MD -MP 
 -MF .deps/perl-core.Tpo -c perl-core.c  -fPIC -DPIC -o .libs/perl-core.o 
perl-core.c: In function 'perl_script_eval': 
perl-core.c:249: error: 'sv_undef' undeclared (first use in this function) 
perl-core.c:249: error: (Each undeclared identifier is reported only once 
perl-core.c:249: error: for each function it appears in.) 
gmake[6]: *** [perl-core.lo] Error 1 
 
gcc version 4.0.0 
perl version 5.8.8 (Originally 5.6.0; I thought it may be a perl problem, so I 
installed the latest; no difference) 
 
Any suggestions? 
 
Thanks 
DM